The invention relates to apparatus for supporting a working platform on a pitched roof.
When roofs are being covered with shingles, or when it is necessary to gain access to roofs in order to replace shingles, it is desirable to be able to dispose adjacent the roof a horizontal working platform on which the roof workers can stand or kneel in order to carry out the necessary placement of shingles. However, supporting such a working platform is fraught with considerable difficulty. Hitherto, roof work has either been conducted from crawl ladders lying flat against the roof, such crawl ladders having at their upper ends a hook section which engages the roof cap, or large scaffolding frameworks have been fixed to the roof, such scaffoldings usually extending across both sides of the roof in order to ensure that they cannot move relative thereto. Whilst crawl ladders are light in weight and can be rapidly placed in position or moved from one working location to another, on very large or steep roofs it may be difficult to provide a ladder of sufficient length which is easily manhandled and it may also be difficult to retain the ladder in position on very steep roofs. Furthermore, from a crawl ladder a worker can only reach a very limited area of the roof, so that it is necessary to move the crawl ladder frequently, and crawl ladders do not provide any suitable place for storing a stack of shingles prior to placing them on the roof. Permanent scaffolding allows ready access to large roof areas, but the erection and dismantling of such scaffolding is very labor-intensive and costly, so that the labor costs in erecting and dismantling the scaffolding may constitute a substantial proportion of a reroofing job. Where only a small proportion of the shingles on a large roof have to be replaced, for example because of storm damage, it is economically impractical to erect permanent scaffolding which will afford access to all the damaged shingles scattered over the entire roof. Finally, the weight of permanent scaffolding may present a problem since the shingles used on most roofs are not very strong and may be damaged by the weight of the scaffolding.
There is thus a need for some way of supporting a working platform on a pitched roof which would provide a large platform, thus providing access to a large section of the roof, but which is suffficiently light in weight not to present any danger of damage to the roof and to be easily manhandled onto the roof. In addition, it is desirable that such a working platform provide sufficient storage space to enable one or more bundles of shingles, tools or other equipment to be stored close at hand for a worker who is covering a roof. Moreover, because such apparatus may be used on roofs having differing pitches, it is desirable that a way be provided of keeping the working platform accurately horizontal regardless of the pitch of the roof. This invention provides such an apparatus.